Add exclude flag to exclude paths

fixtures/excludedpath/file.testdata

@@ -0,0 +1,2 @@
+// Package excludedpath holds test data for the licensing cmd
+package excludedpath

golden/excludedpath/file.go

@@ -0,0 +1,19 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Package excludedpath holds test data for the licensing cmd
+package excludedpath

main.go

@@ -23,6 +23,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/elastic/go-licenser/licensing"
 )
@@ -78,10 +79,27 @@ var (
 	extension          string
 	args               []string
 	headerBytes        []byte
+	exclude            sliceFlag
 	defaultExludedDirs = []string{"vendor", ".git"}
 )
 
+type sliceFlag []string
+
+func (f *sliceFlag) String() string {
+	var s string
+	for _, i := range *f {
+		s += i + " "
+	}
+	return s
+}
+
+func (f *sliceFlag) Set(value string) error {
+	*f = append(*f, value)
+	return nil
+}
+
 func init() {
+	flag.Var(&exclude, "exclude", `path to exclude (can be specified multiple times).`)
 	flag.BoolVar(&dryRun, "d", false, `skips rewriting files and returns exitcode 1 if any discrepancies are found.`)
 	flag.StringVar(&extension, "ext", defaultExt, "sets the file extension to scan for.")
 	flag.Usage = usageFlag
@@ -94,15 +112,15 @@ func init() {
 }
 
 func main() {
-	err := run(args, defaultExludedDirs, extension, dryRun, os.Stdout)
+	err := run(args, exclude, extension, dryRun, os.Stdout)
 	if err != nil && err.Error() != "<nil>" {
-		fmt.Println(err)
+		fmt.Fprint(os.Stderr, err)
 	}
 
 	os.Exit(Code(err))
 }
 
-func run(args, exclDirs []string, ext string, dry bool, out io.Writer) error {
+func run(args, exclude []string, ext string, dry bool, out io.Writer) error {
 	var path = defaultPath
 	if len(args) > 0 {
 		path = args[0]
@@ -112,7 +130,7 @@ func run(args, exclDirs []string, ext string, dry bool, out io.Writer) error {
 		return &Error{err: err, code: exitFailedToStatTree}
 	}
 
-	return walk(path, ext, defaultExludedDirs, dry, out)
+	return walk(path, ext, exclude, dry, out)
 }
 
 func reportFile(out io.Writer, f string) {
@@ -132,7 +150,13 @@ func walk(p, ext string, exclude []string, dry bool, out io.Writer) error {
 			return walkErr
 		}
 
-		if info.IsDir() && stringInSlice(info.Name(), exclude) {
+		var currentPath = cleanPathPrefixes(
+			strings.Replace(path, p, "", 1),
+			[]string{string(os.PathSeparator)},
+		)
+
+		var excludedDir = info.IsDir() && stringInSlice(info.Name(), defaultExludedDirs)
+		if needsExclusion(currentPath, exclude) || excludedDir {
 			return filepath.SkipDir
 		}
 

main_test.go

@@ -105,10 +105,10 @@ func dcopy(src, dest string, info os.FileInfo) error {
 
 func Test_run(t *testing.T) {
 	type args struct {
-		args     []string
-		exclDirs []string
-		ext      string
-		dry      bool
+		args    []string
+		exclude []string
+		ext     string
+		dry     bool
 	}
 	tests := []struct {
 		name       string
@@ -121,10 +121,10 @@ func Test_run(t *testing.T) {
 		{
 			name: "Run a diff prints a list of files that need the license header",
 			args: args{
-				args:     []string{"testdata"},
-				exclDirs: defaultExludedDirs,
-				ext:      defaultExt,
-				dry:      true,
+				args:    []string{"testdata"},
+				exclude: []string{"excludedpath"},
+				ext:     defaultExt,
+				dry:     true,
 			},
 			want: 1,
 			err:  &Error{code: 1},
@@ -142,21 +142,20 @@ testdata/singlelevel/wrapper.go: is missing the license header
 		{
 			name: "Run against an unexisting dir fails",
 			args: args{
-				args:     []string{"ignore"},
-				exclDirs: defaultExludedDirs,
-				ext:      defaultExt,
-				dry:      false,
+				args: []string{"ignore"},
+				ext:  defaultExt,
+				dry:  false,
 			},
 			want: 2,
 			err:  goosPathError(2, "ignore"),
 		},
 		{
 			name: "Run with default mode rewrites the source files",
 			args: args{
-				args:     []string{"testdata"},
-				exclDirs: defaultExludedDirs,
-				ext:      defaultExt,
-				dry:      false,
+				args:    []string{"testdata"},
+				exclude: []string{"excludedpath"},
+				ext:     defaultExt,
+				dry:     false,
 			},
 			want:       0,
 			wantGolden: true,
@@ -169,7 +168,7 @@ testdata/singlelevel/wrapper.go: is missing the license header
 			}
 
 			var buf = new(bytes.Buffer)
-			var err = run(tt.args.args, tt.args.exclDirs, tt.args.ext, tt.args.dry, buf)
+			var err = run(tt.args.args, tt.args.exclude, tt.args.ext, tt.args.dry, buf)
 			if !reflect.DeepEqual(err, tt.err) {
 				t.Errorf("run() error = %v, wantErr %v", err, tt.err)
 				return
@@ -189,7 +188,7 @@ testdata/singlelevel/wrapper.go: is missing the license header
 			if tt.wantGolden {
 				if *update {
 					copyFixtures(t, "golden")
-					if err := run([]string{"golden"}, tt.args.exclDirs, tt.args.ext, tt.args.dry, buf); err != nil {
+					if err := run([]string{"golden"}, tt.args.exclude, tt.args.ext, tt.args.dry, buf); err != nil {
 						t.Fatal(err)
 					}
 				}

path.go

@@ -0,0 +1,54 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package main
+
+import (
+	"os"
+	"strings"
+)
+
+func needsExclusion(path string, exclude []string) bool {
+	for _, excluded := range exclude {
+		excluded = cleanPathSuffixes(excluded, []string{"*", string(os.PathSeparator)})
+		if strings.HasPrefix(path, excluded) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func cleanPathSuffixes(path string, sufixes []string) string {
+	for _, suffix := range sufixes {
+		for strings.HasSuffix(path, suffix) && len(path) > 0 {
+			path = path[:len(path)-len(suffix)]
+		}
+	}
+
+	return path
+}
+
+func cleanPathPrefixes(path string, prefixes []string) string {
+	for _, prefix := range prefixes {
+		for strings.HasPrefix(path, prefix) && len(path) > 0 {
+			path = path[len(prefix):]
+		}
+	}
+
+	return path
+}